Well, first off it probably isn't very safe to run X as root. You'd be better off logging into X as yourself and launching teminal windows to "su"
to root if you need it.
Ok, stepping off the soapbox now. You might want to take a look through root's .xinitrc file and
remove the afterstep references (or better yet, just comment them out until you're sure everything works). All you truly need in there (I believe) is a reference to "startkde", which should be in root's $PATH. I'm sure someone will correct me if I'm wrong - not a big KDE fan